AT5221 [ABC140C] Maximal Value 题解

Content 有一个长度为 $n$ 的数列 $A$ 未知,已知一个数列 $B=\{b_1,b_2,...,b_{n-1}\}$,且满足 $b_i\geqslant \max\{a_i,a_{i+1}\}$.求原数列 $A$ 的元素和的最大值. 数据范围:$n\in[2,100],b_i\in[0,10^5]$. Solution 很显然,$a_i$ 的最大值为 $\min\{b_i,b_{i-1}\}$,所以先逐个更新 $a_i$,然后直接求和即可. Cod…

算法与数据结构基础 - 数组(Array)

数组基础数组是最基础的数据结构,特点是O(1)时间读取任意下标元素,经常应用于排序(Sort).双指针(Two Pointers).二分查找(Binary Search).动态规划(DP)等算法.顺序访问数组.按下标取值是对数组的常见操作. 相关LeetCode题: 905. Sort Array By Parity 题解 922. Sort Array By Parity II 题解 977. Squares of a Sorted Array 题解 1150. Check If a…

LeetCode题解：(221) Maximal Square

题目说明 Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 Return 4. 题目分析我采用的方法比较笨拙,就是对于矩阵中的每一个元素,以反"L"…

LeetCode85 Maximal Rectangle java题解

public static int maximalRectangle(char[][] matrix) { int rowNum=matrix.length; if(rowNum==0) return 0; int columnNum=matrix[0].length; int[][] height=new int[rowNum][columnNum+1]; int maxarea=0; for(int i=0;i<rowNum;i++) { for(int j=0;j<columnNum;j…

题解 [CF803C] Maximal GCD

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Luogu codeforces 前言模拟赛原题.. 好好一道送分被我硬打成爆蛋.. $\sf{Solution}$ 看了一波数据范围,感觉能 dfs 骗分. 骗成正解了. 大概就是将这个 $n\times n$ 的矩阵全扫一遍,可以选择填 $1$ 或不填.回溯一下就行啦. 位置问题假设现在的坐标为 $(x,y)$ 若 $x>n$ ,则结束 dfs ,比较一下矩阵字典序,较为简单不题. 若 $y>n$ ,则 $x→x+1,y=1$ ,即跳到下一行第一位. 对称处…

求解最大矩形面积 — leetcode 85. Maximal Rectangle

之前切了道求解最大正方形的题,题解猛戳这里.这道题 Maximal Rectangle 题意与之类似,但是解法完全不一样. 先来看这道题 Largest Rectangle in Histogram,如果暴力求解,可以枚举每个点为最小值,向两边扩展,复杂度 O(n^2).我们可以维护一个栈,从而将复杂度降低到 O(n),这个栈的思维非常巧妙,参考了 discuss,我是完全想不出来(或者说忘记了).具体代码可以猛戳这里. 2016-08-07 补:stack 数组维护的是一个单调递增的数组,…

LeetCode OJ 题解

博客搬至blog.csgrandeur.com,cnblogs不再更新. 新的题解会更新在新博客:http://blog.csgrandeur.com/2014/01/15/LeetCode-OJ-Solution/ ———————————————————————————————————————— ———————————————————————————————————————— LeetCode OJ 题解 LeetCode OJ is a platform for preparing tech…

LeetCode Maximal Square

原题链接在这里:https://leetcode.com/problems/maximal-square/ 这是一道DP题,存储历史信息是到当前点能有的最大square, 用二维数组dp存储. 更新方式是若当前点为0,则不更新,若当前点为1,则取上dp[i-1][j], 左dp[i][j-1], 左上dp[i-1][j-1]的中的最小值,开根号加一,最后平方为dp[i][j]. 初始第一行和第一列,为'1'的时候填成1. Note: 1. 给的matrix数组是char, 所以比较时是根char…

2014年亚洲区域赛北京赛区现场赛A,D,H,I,K题解(hdu5112,5115,5119,5220,5122)

转载请注明出处: http://www.cnblogs.com/fraud/ ——by fraud 下午在HDU上打了一下今年北京区域赛的重现,过了5题,看来单挑只能拿拿铜牌,呜呜. 先将这五题的题解放上来,剩余题目等搞出来再补上 A题 A Curious Matt Time Limit: 2000/2000 MS (Java/Others) Memory Limit: 512000/512000 K (Java/Others) Problem Description T…

LeetCode之“动态规划”：Maximal Square && Largest Rectangle in Histogram && Maximal Rectangle

1. Maximal Square 题目链接题目要求: Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: Return 4. 在GeeksforGeeks有一个解决该问题的方法: 1) Construct a sum matrix S[R…

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突然很想刷刷题,LeetCode是一个不错的选择,忽略了输入输出,更好的突出了算法,省去了不少时间. dalao们发现了任何错误,或是代码无法通过,或是有更好的解法,或是有任何疑问和建议的话,可以在对应的随笔下面评论区留言,我会及时处理,在此谢过了. 过程或许会很漫长,也很痛苦,慢慢来吧. 编号题名过题率难度 1 Two Sum 0.376 Easy 2 Add Two Numbers 0.285 Medium 3 Longest Substring Without Repeating C…

[PAT] 1142 Maximal Clique（25 分）

1142 Maximal Clique(25 分) A clique is a subset of vertices of an undirected graph such that every two distinct vertices in the clique are adjacent. A maximal clique is a clique that cannot be extended by including one more adjacent vertex. (Quoted fr…

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A. Friends Meeting time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Two friends are on the coordinate axis Ox in points with integer coordinates. One of them is in the point x1 = a, another…

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接着是C,D的题解 C. Tourist Problem Iahub is a big fan of tourists. He wants to become a tourist himself, so he planned a trip. There are n destinations on a straight road that Iahub wants to visit. Iahub starts the excursion from kilometer 0. The n destina…

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A. Sea Battle time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output In order to make the "Sea Battle" game more interesting, Boris decided to add a new ship type to it. The ship consists of…

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Codeforces 340B - Maximal Area Quadrilateral (计算几何)

Codeforces Round #198 (Div. 2) 题目链接:Maximal Area Quadrilateral Iahub has drawn a set of $n$ points in the cartesian plane which he calls "special points". A quadrilateral is a simple polygon without self-intersections with four sides (also cal…

F - Maximal Intersection --------暴力求解题

You are given n segments on a number line; each endpoint of every segment has integer coordinates. Some segments can degenerate to points. Segments can intersect with each other, be nested in each other or even coincide. The intersection of a sequenc…

CodeChef-LECOINS Little Elephant and Colored Coins 题解

CodeChef-LECOINS Little Elephant and Colored Coins Little Elephant and Colored Coins The Little Elephant from the Zoo of Lviv very likes coins. But most of all he likes colored coins. He has N types of coins, numbered from 1 to N, inclusive. The coin…

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我要举报本次校赛出题人的消极出题!!! 官方题解请戳:http://3.scnuacm2015.sinaapp.com/?p=89(其实就是一堆代码没有题解) A. 树链剖分数据结构板题题目大意:我没看,看不懂. 基本思路:我不会. 参考代码:找Oyk老师和Czj老师去. B. The background of water problem 题目大意(大写加粗的水题):给定$N$个学生和他们$K$个科目的成绩$S_i$,再给出各科目$K_i$的权重顺序$Q_i$,求排名之后,拥有id为$X$的…

noip2016十连测题解

以下代码为了阅读方便,省去以下头文件: #include <iostream> #include <stdio.h> #include <math.h> #include <string.h> #include <time.h> #include <stdlib.h> #include <string> #include <bitset> #include <vector> #include <…

[LeetCode] Maximal Square 最大正方形

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area. For example, given the following matrix: 1 0 1 0 0 1 0 1 1 1 1 1 0 0 1 0 Return 4. Credits:Special thanks to @Freezen for adding this pr…